Surface maintenance vehicles are well known. These vehicles and devices may be self-powered, towed, or pushed, and/or manually powered and may carry a human operator during cleaning operations. Such vehicles include scrubbers, extractors, sweepers and vacuums, as well as combinations thereof, intended for cleaning, scrubbing, wiping and/or drying a portion of a substantially flat surface both indoors and outdoors. These devices typically include a source of cleaning solution, solution applying means for distributing cleaning solution onto the floor surface, scrubbing means for engaging a wetted floor surface and a vacuum system for removing soiled cleaning solution from the floor surface. The cleaning solution is typically supplied to the floor surface through or near rotary scrub brushes operating from a lower portion of the vehicle. The vacuum system typically includes one or more squeegee elements, such as disclosed in U.S. Pat. Nos. 6,895,633; 6,705,332 and 6,602,018, each being incorporated by referenced herein.
The squeegee assembly of such prior art cleaning vehicles often mounts at or near the rear of the surface maintenance vehicle to direct the solution to a removal location where the solution (including suspended dirt, particles and contaminants) is removed. The squeegee assembly may include a squeegee supporting member of generally arcuate configuration with two squeegee blades spaced apart and affixed to the supporting member to promote consistent contact with the surface to be cleaned and wiped.
In some prior art cleaning vehicles having two squeegee blades, a vacuum source may couple to the wiping assembly to lift the loaded cleaning solution from the space between the blades to a remote reservoir or other collection unit. The squeegee assembly is often sufficiently wide to at least fully cover the path width of the scrub brushes and/or the wheels of the cleaning vehicle. The ends of the squeegee assembly tend to be exposed at the sides of the vehicle and are therefore potentially vulnerable to contact with stationary objects which might be encountered during operation of the vehicle during cleaning operations and when transporting the vehicle between cleaning operations.
The squeegee blades in these types of machines are often a wear/service item. As the blades wear, the ability of the machine to pick up soiled cleaning solution and/or water is diminished. In some particularly harsh environments, squeegee blades are replaced multiple times during the life of the machine. Many times this is done by the operator in the field where the availability of tools is limited. Some prior art machines provide thumb screws for retaining the squeegee blades.
Tennant Company's model 433 Walk Behind Scrubber has included removable squeegee blades and retainers. In this design, the retainers and blades are connected together via fasteners. The design provides for tool-less blade exchange by increasing the clearance around the blades, so the blades could be pushed or pulled within a retainer-receiving channel.
Some prior art squeegee assembly couplings use a compliant bushing that has a portion of the bushing captured by the squeegee assembly and the remainder of the bushing captured in the squeegee suspension. A threaded fastener is used to secure the bushing between the squeegee assembly and the squeegee suspension. The pocket profile in the squeegee suspension allows for the through hardware to be released through an open ended slot profile and also incorporates a pocket for the portion of the compliant bushing. The through hardware will hold the assembly together for normal operation.
The threaded hardware of the prior art is difficult and time-consuming to work with, and is a burden to work with as it is located in a dirty environment and the threads become contaminated. In the past, squeegee disassembly and replacement of the blades has been a tedious, time consuming task. Thus, there is a need for an improved squeegee assembly which has improved assembly and disassembly features, possibly including an improved releasable coupling.